It is known that there are an infinite number of worlds, simply because there is an infinite amount of space for them to be in. However, not every one of them is inhabited. Therefore, there must be a finite number of inhabited worlds. Any finite number divided by infinity is as near to nothing as makes no odds, so the average population of all the planets in the Universe can be said to be zero. From this it follows that the population of the whole Universe is also zero, and that any people you may meet from time to time are merely the products of a deranged imagination.
If they were going to be like that, then I just wished they hadn't actually been German. It was too easy. Too obvious. It was like coming across an Irishman who actually was stupid, a mother-in-law who actually was fat, or an American businessman who actually did have a middle initial and smoked a cigar. You feel as if you are unwillingly performing in a music-hall sketch and wishing you could rewrite the script. If Helmut and Kurt had been Brazilian or Chinese or Latvian or anything else at all, they could then have behaved in exactly the same way and it would have been surprising and intriguing and, more to the point from my perspective, much easier to write about. Writers should not be in the business of propping up stereotypes. I wondered what to do about it, decided that they could simply be Latvians if I wanted, and then at last drifted off peacefully to worrying about my boots.
For Children: You will need to know the difference between Friday and a fried egg. It's quite a simple difference, but an important one. Friday comes at the end of the week, whereas a fried egg comes out of a chicken. Like most things, of course, it isn't quite that simple. The fried egg isn't properly a fried egg until it's been put in a frying pan and fried. This is something you wouldn't do to a Friday, of course, though you might do it on a Friday. You can also fry eggs on a Thursday, if you like, or on a cooker. It's all rather complicated, but it makes a kind of sense if you think about it for a while.
The Babel fish is small, yellow, leechlike, and probably the oddest thing in the Universe. It feeds on brainwave energy received not from its own carrier but from those around it. It absorbs all unconscious mental frequencies from this brainwave energy to nourish itself with. It then excretes into the mind of its carrier a telepathic matrix formed by combining the conscious thought frequencies with nerve signals picked up from the speech centers of the brain which has supplied them. The practical upshot of all this is that if you stick a Babel fish in your ear you can instantly understand anything said to you in any form of language. The speech patterns you actually hear decode the brainwave matrix which has been fed into your mind by your Babel fish.